File System Types

Solaris Live Upgrade distinguishes between two file system types:
critical file systems and shareable. The following table describes these file
system types.

File System Type

Description

Examples and More Information

Critical file systems

Critical file systems are required by the Solaris OS. These file systems
are separate mount points in the vfstab of the active
and inactive boot environments. These file systems are always copied from
the source to the inactive boot environment. Critical file systems are sometimes
referred to as nonshareable.

Examples are root (/), /usr, /var, or /opt.

Shareable file systems

Shareable file systems are user-defined files such as /export that
contain the same mount point in the vfstab in both the
active and inactive boot environments. Therefore, updating shared files in
the active boot environment also updates data in the inactive boot environment.
When you create a new boot environment, shareable file systems are shared
by default. But you can specify a destination slice and then the file systems
are copied.